1.Identification of a novel germline BRCA2 variant in a male with breast cancer.
Chinese Journal of Medical Genetics 2022;39(3):330-333
OBJECTIVE:
To explore the genetic basis for a male with breast cancer and a sister who had deceased of the disease.
METHODS:
Medical and family history of the proband was collected. Next-generation sequencing was carried out to detect potential variant associated with breast cancer, and Sanger sequencing was used to verify the result.
RESULTS:
The proband was found to harbor a novel heterozygous c.6018dupT variant of the BRCA2 gene which may cause premature termination of mRNA translation, resulting in a truncated protein. Combined with the family history, the variant was deduced to be a germline mutation. Based on the American College of Medical Genetics and Genomics standards and guidelines, c.6018dupT variant of BRCA2 gene was predicted to be pathogenic (PVS1+PM1/2+PP4).
CONCLUSION
The germline variant of the BRCA2 gene probably underlay the breast cancer in this pedigree.
BRCA2 Protein/genetics*
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Breast Neoplasms, Male/genetics*
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Genes, BRCA2
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Genomics
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Germ Cells
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Germ-Line Mutation
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Humans
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Male
4.Analysis of BRCA2 gene mutations among familial and/or early-onset breast cancer patients in eastern Shandong of China.
Zhong-liang MA ; Ming-zhi CAO ; Wen-feng LI
Chinese Journal of Medical Genetics 2008;25(2):195-198
OBJECTIVETo investigate the prevalence of BRCA2 gene mutations among familial and/or early-onset breast cancer patients in eastern Shandong of China.
METHODSFifty-two familial and/or early-onset breast cancer patients from unrelated family were analyzed. Genomic DNA was collected from the peripheral blood mononuclear cells, the coding sequences and exon-intron boundaries of BRCA2 gene were screened using denaturing high performance liquid chromatography (DHPLC), and the abnormal fragments were confirmed with direct DNA sequencing.
RESULTSThree mutations (5.8%) in BRCA2 gene were identified. They were 2001del TTAT, 4099C to T and 5873C to A. To our knowledge, all of them were firstly found in Chinese population. Furthermore, all the three mutations (12%) were identified in familial breast cancer patients, and none was in the early-onset patients.
CONCLUSIONBRCA2 may play an important role in the familial breast cancer in eastern Shandong Chinese population, but not in the early-onset breast cancer. It is necessary to give genetic test to familial breast cancer patients in this population.
Adult ; BRCA2 Protein ; genetics ; Breast Neoplasms ; genetics ; China ; Chromatography, High Pressure Liquid ; Female ; Humans ; Mutation ; Polymerase Chain Reaction
5.BRCA1 and BRCA2 gene mutations of familial breast cancer from Shanghai in China.
Chuan-gui SONG ; Zhen HU ; Wen-tao YUAN ; Gen-hong DI ; Zhen-zhou SHEN ; Wei HUANG ; Zhi-min SHAO
Chinese Journal of Medical Genetics 2006;23(1):27-31
OBJECTIVETo investigate the prevalence of BRCA1 and BRCA2 gene mutations among breast cancer patients with affected relatives in Shanghai of China.
METHODSThirty-five breast cancer patients who had at least one first-degree relative affected were analyzed, among whom 13 patients suffered from breast cancer at age of less than 40 years. A comprehensive BRCA1 and BRCA2 mutation analysis was performed through denaturing high-performance liquid chromatography (DHPLC) and subsequent DNA direct sequencing.
RESULTSFour mutations in BRCA1 gene, including 2 novel splice-site mutations (IVS17-1G>T, IVS21+1G>C) and 2 frameshift mutations (1100delAT; 5640delA) were identified. One frameshift mutation (5802delAATT) was detected in exon 11 of BRCA2. Additional 12 novel single nucleotide polymorphisms(SNPs) were detected, including a novel unclassified variant and 7 novel intronic variants in BRCA1, and 4 novel intronic variants in BRCA2, with which all caused no alteration of amino acid coding. The mutation frequency of BRCA1 and BRCA2 in patients with family history was 11.4% and 2.9%, respectively.
CONCLUSIONTwo novel mutations in BRCA1 may be mutations characterized to familial breast cancer of Chinese Shanghai population. The BRCA2 may contribute to mutation less than BRCA1 in familial breast cancer. Our data contribute to information on mutation spectrum of BRCA gene in Chinese population and also offer a recommended screening mode for clinical genetic testing policy in China.
Asian Continental Ancestry Group ; genetics ; BRCA1 Protein ; genetics ; BRCA2 Protein ; genetics ; Breast Neoplasms ; genetics ; China ; DNA, Neoplasm ; analysis ; Family Health ; Female ; Humans ; Point Mutation ; Polymorphism, Single Nucleotide
6.Progress in molecular genetics of correlating genes of breast cancer.
Yang WU ; Li YANG ; Yuquan WEI
Chinese Journal of Medical Genetics 2002;19(2):152-155
Good progress has been made in the researches on correlating genes of breast cancer in recent years. Quite a few kinds of genes such as susceptibility gene, oncogene and tumor suppressor genes have been found with implications for diagnosis, therapy and prognosis. Abnormality of breast cancer susceptibility gene (BRCA) is of great significance, especially in the development of breast cancer.
BRCA1 Protein
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genetics
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BRCA2 Protein
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genetics
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Breast Neoplasms
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genetics
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Cyclin-Dependent Kinase Inhibitor p16
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genetics
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Cyclin-Dependent Kinase Inhibitor p21
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Cyclins
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genetics
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Female
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Humans
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Mutation
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Neoplasm Proteins
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genetics
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Proto-Oncogene Proteins
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genetics
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Tumor Suppressor Protein p53
;
genetics
7.Effect of BRCA2 mutation on familial breast cancer survival: A systematic review and meta-analysis.
Jun SHAO ; Jie YANG ; Jun-nai WANG ; Long QIAO ; Wei FAN ; Qing-lei GAO ; Yao-jun FENG
Journal of Huazhong University of Science and Technology (Medical Sciences) 2015;35(5):629-634
Reports of BRCA2 genetic mutations on the prognosis of familial breast cancer (BC) patients have been contradictory. True difference in survival, if it exists, would have important implications for genetic counseling and in treatment of hereditary BC. The purpose of this study was to compare overall survival rate (OSR) among BRCA2 mutation carriers, non-carriers and sporadic BC patients. We searched the PUBMED and EMBASE databases and retrieved 4529 articles using keywords that included breast cancer, BRCA, prognosis and survival. Nine articles were selected for systematic review and among them 6 were included in our meta-analysis. We used the fixed and random effect models to calculate the summary odds ratio (OR) and corresponding 95% confidence interval (CI). BRCA2 mutation carriers had significantly higher long-term OSR than non-carriers (OR=0.69 [95% CI=0.5-0.95]), while both short-term and long-term OSR of BRCA2 mutation carriers did not differ from those of patients with sporadic disease (OR=1.11 [95% CI=0.74-1.65]; 0.85 [95% CI=0.38-1.94], respectively). For BC-specific survival rate (BCSSR), BRCA2 mutation carriers had a similar BCSSR to the non-carriers (OR=0.61 [95% CI=0.28-1.34]). There was no significant difference in disease-free survival (DFS) between BRCA2 mutation carriers and patients with sporadic disease. Our results suggest that BRCA2 mutation increases long-term OSR in hereditary BC, which reminds us a new prospect of management of the disease.
BRCA2 Protein
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genetics
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Breast Neoplasms
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genetics
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mortality
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pathology
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Female
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Gene Expression
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Genetic Counseling
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Genetic Predisposition to Disease
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Humans
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Mutation
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Odds Ratio
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Prognosis
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Survival Analysis
8.Impaired phosphorylation and mis-localization of Bub1 and BubR1 are responsible for the defective mitotic checkpoint function in Brca2-mutant thymic lymphomas.
Experimental & Molecular Medicine 2003;35(5):448-453
Breast cancer susceptibility gene, BRCA2, is a tumor suppressor and individuals who inherit one defected copy of BRCA2 allele experience early onset breast cancer or ovarian cancer accompanied by the loss of the wild type allele. Mouse model for Brca2 mutation shows growth retardation and paradoxical occurrence of thymic lymphomas. Thymic lymphomas from Brca2-mutant mice harbor mutations in p53, Bub1, and BubR1, which function as mitotic checkpoint proteins. Therefore, interplay between Brca2 and mitotic checkpoint has been suggested in the maintenance of genetic fidelity, although it has not been assessed whether the unique mutations in Bub1 and BubR1 found in Brca2-mutant mice are responsible for the abolishment of mitotic checkpoint function. This report demonstrates that Bub1 and BubR1 mutant proteins from Brca2(-/-)thymic lymphomas have defects in the phosphorylation and kinetochore localization after spindle damage. Thus, the mutations of Bub1 and BubR1 found in Brca2- mutant mice indeed are responsible for the chromosome instability in Brca2-mutated tumors.
Animals
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BRCA2 Protein/*genetics/*metabolism
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Cell Cycle Proteins
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Cell Transformation, Neoplastic/metabolism
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Mice
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*Mitosis
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Mutation/*genetics
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Phosphorylation
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Protein Kinases/*metabolism
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Protein Transport
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Support, Non-U.S. Gov't
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T-Lymphocytes/metabolism
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Thymus Neoplasms/genetics/*pathology
10.BRCA1/2 associated hereditary breast cancer.
Li-song TENG ; Yi ZHENG ; Hao-hao WANG
Journal of Zhejiang University. Science. B 2008;9(2):85-89
Breast cancer is one of the leading causes of death in women today. Some of the patients are hereditary, with a large proportion characterized by mutation in BRCA1 and/or BRCA2 genes. In this review, we provide an overview of these two genes, focusing on their relationship with hereditary breast cancers. BRCA1/2 associated hereditary breast cancers have unique features that differ from the general breast cancers, including alterations in cellular molecules, pathological bases, biological behavior, and a different prevention strategy. But the outcome of BRCA1/2 associated hereditary breast cancers still remains controversial; further studies are needed to elucidate the nature of BRCA1/2 associated hereditary breast cancers.
Apoptosis Regulatory Proteins
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BRCA1 Protein
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genetics
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physiology
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BRCA2 Protein
;
genetics
;
physiology
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Breast Neoplasms
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genetics
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metabolism
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Disease Progression
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Female
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Gene Expression Regulation, Neoplastic
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Genetic Diseases, Inborn
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Genetic Predisposition to Disease
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Humans
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Mutation
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Prognosis